Composite porous fabric-impervious film article

ABSTRACT

A composite fabric structure that has a high resistance to fluid flow therethrough in one direction and a substantially reduced resistance to fluid flow therethrough in the opposite direction.

I United States Patent 1 1 1111 3,930,096 Gilpatrick [4 1 Dec. 30, 1975 [54] COMPOSITE POROUS 3,301,168 11/1967 Schindler et al 137/5l2.15 FABRICJMPERVIOUS FILM ARTICLE 3,446,208 5/1969 Fukuda 128/ 156 3,568,829 3/1971 Brady 206/820 Inventor: Michael Gilpatrick, Chesnee, 3,616,802 11 1971 Marinaccio.. 55 417 S.C. 3,654,060 4/1972 Goldman 161/109 Assigneez Deering Mimken Research 3,858,605 1/1975 Bauer et a1. 157/51215 Corporation, Spartanburg, SC. [22] Filed: Apr. 15, 1974 Primary ExaminerGeorge F. Lesmes Assistant Examiner-R. J. Roche [21] Appl 460983 Attorney, Agent, or Firm-Earle R. Marden; H.

William Petty [52] US. Cl. 428/255; 137/512.15; 137/525;

55/417; 210/504; 210/506; 428/114; 428/198; 428/293; 428/294 51 nt. c1. F16K 15 00; B32B 3/00 ABSTRACT [58] Field of Search 161/146, 109, 112, 166;

165/19, 20, 21; 137/512.l5 525; 156/256, A composite fabric structure that has a high resistance 257, 259, 270, 271; 210/504; 55/417; to fluid flow therethrough in one direction and a sub- 206/393; 428/114, 255, 198, 293, 294 stantially reduced resistance to fluid flow therethrough in the opposite direction. [56] References Cited UNITED STATES PATENTS l Claim, 4 Drawing Figures Bunyan 128/156 US. Patent Dec.30, 1975 Sheet 1 of2 3,930,096

AIR PERMEABILITY (SCFM PER FTZ) US. Patent Dec. 30, 1975 Sheet20f2 3,930,096

FORWARD DIRECTION\ x x? BACKWARD l 24 ,D|RECT|ON I I o \V' I I Z o.

I X! I d PRESSURE DROP (INCHES H2O) TYPICAL RESPONSE CURVE COMPOSITE POROUS FABRIC-IMPERVIOUS FILM ARTICLE It is the object of the invention to provide a new and novel fabric which will readily allow fluid flow therethrough in one direction but inhibits fluid flow therethrough in the opposite direction.

Other objects and advantages of the invention will become readily apparent as the specification proceeds to describe the invention with reference to the accom panying drawings, in which:

FIG. 1 is a top view of the new and novel fabric;

FIG. 2 is a cross-sectional view of the fabric on line 2-2 of FIG. 1;

FIG. 3 is a perspective view of the apparatus employed to manufacture the fabric shown in FIGS. 1 and 2; and

FIG. 4 is a graphic representation of the fluid flow in both directions through the disclosed fabric.

In the preferred form of the invention the fabric consists of an open mesh type of woven, non-woven or knitted substrate to which is laminated a non-permeable film material. It should be kept in mind that when fluid flow is discussed it refers to liquid, as well as gaseous flow. Also, the composite fabric is not restricted to any particular fabric construction so long as it meets the requirement that the fluid flow in one direction therethrough is substantially greater than the fluid flow in the opposite direction.

Fabric in FIGS. 1 and 2 basically consists of a base layer of a loosely woven 65% polyester 30% cotton fabric 12- to which is laminated at long narrow places 14 a non-permeable film material 16 such as polyethylene. Then the film material is slit longitudinally at 18 to form a series of flaps 20 secured at the longitudinal edges by the strips 14.

Looking at FIGS. 2 and 4 it can be seen that when a fluid is passed upwardly from the bottom of FIG. 2 to the top, that the flaps 20 will be forced upwardly thereby allowing a large flow rate of fluid to pass therethrough as shown by curve 22 on the graph shown in FIG. 4. Conversely, if the flow should be reversed, the pressure of the fluid will press the flaps 20 against the substrate 12 to substantially cut down the flow of fluid therethrough, as evidenced by curve 24 on FIG. 4. As discussed previously the flow differential between the two will depend -on the permeability of the individual laminated fabrics, fabric construction, etc.

FIG. 3 illustrates the preferred method of constructing the above fabric. A woven fabric 12 is supplied from a supply roll 26 and is brought together with polyethylene web material 16 at a point between the finned pressure roller 28 and the contact heater 30. The combination of the heat from the heater 30 and the pres sure of the fins 32 provide the laminated strips 14. From the pressure roller the combined fabric is delivered to the slitting knives 34 where the film material is slit at 18 to provide the flaps 20. Then the combined fabric is guided under idler guide roll 36 to the take-up roll 40.

It can be seen that the herein disclosed fabric has definite use where it is desired to allow free flow of fluid in one direction but inhibited fluid flow in the opposite direction. It can be seen that such fabric could be used as a check valve, relief dampers, etc.

Although the preferred embodiment of the invention has been described specifically, it is contemplated that many changes may be made without departing from the scope or spirit of the invention, and it is desired that the invention be limited only by the scope of the claims.

That which is claimed is:

l. A novel fabric construction comprising: a first layer of porous fabric permeable material and a second layer of substantially impervious film material being heat sealed to said first layer at a plurality of elongated positions to said first layer, said layers of material being unconnected between said plurality of elongated spaced heat sealed positions, said second layer of material being severed between said heat sealed positions to provide a pair of contiguous elongated flap members. 

1. A NOVEL FABRIC CONSTRUCTION COMPRISING: A FIRST LAYER OF POROUS FABRIC PERMEABLE MATERIAL AND A SECOND LAYER OF SUBSTANTIALLY IMPERVIOUS FILM MATERIAL BEING HEAT SEALED TO SAID FIRST LAYER AT A PLURALITY OF ELONGATED POSITIONS TO SAID FIRST LAYER, SAID LAYERS OF MATERIAL BEING UNCONNECTED BETWEEN SAID PLURALITY OF ELONGATED SPACED HEAT SEALED POSITIONS, SAID SECOND LAYER OF MATERIAL BEING SEVERED BETWEEN SAID HEAT SEALED POSITIONS TO PROVIDE A PAIR OF CONTIGUOUS ELONGATED FLAP MEMBERS. 